exception Success of B.t Terms.bag * int * B.t Terms.clause
let debug s = prerr_endline (Lazy.force s);;
- (* let debug _ = ();; *)
+ let debug _ = ();;
let enable = true;;
let rec list_first f = function
in
aux bag pos ctx id lit t
;;
-
- let build_clause bag filter rule t subst id id2 pos dir clause_ctx =
+
+ let visit bag pos ctx id lit t f =
+ let rec aux bag pos ctx id subst lit = function
+ | Terms.Leaf _ as t ->
+ let bag,subst,t,id,lit = f bag t pos ctx id lit
+ in assert (subst=[]); bag,t,id,lit
+ | Terms.Var i as t ->
+ let t= Subst.apply_subst subst t in
+ bag,t,id,lit
+ | Terms.Node (hd::l) ->
+ let bag, l, _, id,lit =
+ List.fold_left
+ (fun (bag,pre,post,id,lit) t ->
+ let newctx = fun x -> ctx (Terms.Node (pre@[x]@post)) in
+ let newpos = (List.length pre)::pos in
+ let bag,newt,id,lit = aux bag newpos newctx id subst lit t in
+ if post = [] then bag, pre@[newt], [], id, lit
+ else bag, pre @ [newt], List.tl post, id, lit)
+ (bag, [hd], List.map (Subst.apply_subst subst) (List.tl l), id, lit) l
+ in
+ let bag,subst,t,id1,lit = f bag (Terms.Node l) pos ctx id lit
+ in
+ if id1 = id then (assert (subst=[]); bag,t,id,lit)
+ else aux bag pos ctx id1 subst lit t
+ | _ -> assert false
+ in
+ aux bag pos ctx id [] lit t
+ ;;
+
+ let build_clause ~fresh bag maxvar filter rule t subst id id2 pos dir clause_ctx =
let proof = Terms.Step(rule,id,id2,dir,pos,subst) in
let t = Subst.apply_subst subst t in
if filter subst then
| t -> Terms.Predicate t
in
let nlit,plit = clause_ctx literal in
- let bag, uc =
- Terms.add_to_bag (0, nlit, plit, Terms.vars_of_term t, proof) bag
+ let cl = (0, nlit, plit, [], proof) in
+ let vl = Clauses.vars_of_clause cl in
+ let cl,maxvar =
+ if fresh then Clauses.fresh_clause ~subst maxvar (0, nlit, plit, vl, proof)
+ else (0,nlit,plit,vl,proof),maxvar
+ in
+ let bag, cl =
+ Terms.add_to_bag cl bag
in
- Some (bag, uc, literal)
+ debug (lazy (Pp.pp_clause cl));
+ Some (bag, maxvar, cl, literal)
else
((*prerr_endline ("Filtering: " ^ Pp.pp_foterm t);*)None)
;;
let prof_build_clause = HExtlib.profile ~enable "build_clause";;
- let build_clause bag filter rule t subst id id2 pos x =
- prof_build_clause.HExtlib.profile (build_clause bag filter rule t subst id id2 pos) x
+ let build_clause ~fresh bag maxvar filter rule t subst id id2 pos x =
+ prof_build_clause.HExtlib.profile
+ (build_clause ~fresh bag maxvar filter rule t subst id id2 pos) x
;;
prof_demod.HExtlib.profile (demod table varlist) x
;;
+ let mydemod table varlist subterm =
+ let cands =
+ prof_demod_r.HExtlib.profile
+ (IDX.DT.retrieve_generalizations table) subterm
+ in
+ list_first
+ (fun (dir, is_pos, pos, (id,nlit,plit,vl,_)) ->
+ match (nlit,plit) with
+ | [],[(lit,_)] ->
+ (match lit with
+ | Terms.Predicate _ -> assert false
+ | Terms.Equation (l,r,_,o) ->
+ let side, newside = if dir=Terms.Left2Right then l,r else r,l in
+ try
+ let subst =
+ prof_demod_u.HExtlib.profile
+ (Unif.unification (* (varlist@vl) *) varlist subterm) side
+ in
+ let iside =
+ prof_demod_s.HExtlib.profile
+ (Subst.apply_subst subst) side
+ in
+ let inewside =
+ prof_demod_s.HExtlib.profile
+ (Subst.apply_subst subst) newside
+ in
+ if o = Terms.Incomparable || o = Terms.Invertible then
+ let o =
+ prof_demod_o.HExtlib.profile
+ (Order.compare_terms inewside) iside in
+ (* Riazanov, pp. 45 (ii) *)
+ if o = Terms.Lt then
+ Some (newside, subst, id, dir)
+ else
+ ((*prerr_endline ("Filtering: " ^
+ Pp.pp_foterm side ^ " =(< || =)" ^
+ Pp.pp_foterm newside ^ " coming from " ^
+ Pp.pp_unit_clause uc );*)None)
+ else
+ Some (newside, subst, id, dir)
+ with FoUnif.UnificationFailure _ -> None)
+ | _ -> assert false)
+ (IDX.ClauseSet.elements cands)
+ ;;
+
+ let ctx_demod table vl clause_ctx bag t pos ctx id lit =
+ match mydemod table vl t with
+ | None -> (bag,[],t,id,lit)
+ | Some (newside, subst, id2, dir) ->
+ let inewside = Subst.apply_subst subst newside in
+ match build_clause ~fresh:false bag 0 (fun _ -> true)
+ Terms.Demodulation (ctx inewside) subst id id2 pos dir clause_ctx
+ with
+ | None -> assert false
+ | Some (bag,_,(id,_,_,_,_),lit) ->
+ (bag,subst,newside,id,lit)
+ ;;
+
+ let rec demodulate bag (id,nlit,plit,vl,proof) table =
+ let rec demod_lit ~jump_to_right bag id lit clause_ctx =
+ (match lit with
+ | Terms.Predicate t -> assert false
+ | Terms.Equation (l,r,ty,_) ->
+ let bag,l,id1,lit =
+ visit bag [2]
+ (fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; x; r ]) id lit l
+ (ctx_demod table vl clause_ctx)
+ in
+ let bag,_,id2,lit =
+ visit bag [3]
+ (fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; l; x ]) id1 lit r
+ (ctx_demod table vl clause_ctx)
+ in
+ bag,id2,lit)
+ in
+ let nlit,_,bag,id = if nlit = [] then nlit,[],bag,id
+ else List.fold_left
+ (fun (pre,post,bag,id) (lit,sel) ->
+ let bag, id, lit =
+ demod_lit ~jump_to_right:false bag id lit (fun l -> pre@[l,sel]@post,plit)
+ in
+ if post=[] then pre@[(lit,sel)],[],bag,id
+ else pre@[(lit,sel)],List.tl post,bag,id)
+ ([],List.tl nlit, bag, id) nlit
+ in
+ let _,_,bag,id = if plit = [] then plit,[],bag,id
+ else List.fold_left
+ (fun (pre,post,bag,id) (lit,sel) ->
+ let bag, id, lit =
+ demod_lit ~jump_to_right:false bag id lit (fun l -> nlit,pre@[l,sel]@post)
+ in
+ if post=[] then pre@[(lit,sel)],[],bag,id
+ else pre@[(lit,sel)],List.tl post,bag,id)
+ ([],List.tl plit, bag, id) plit
+ in
+ let cl,_,_ = Terms.get_from_bag id bag in
+ bag,cl
+ ;;
+
let parallel_demod table vl clause_ctx bag t pos ctx id lit =
match demod table vl t with
| None -> (bag,t,id,lit)
| Some (newside, subst, id2, dir) ->
- match build_clause bag (fun _ -> true)
+ match build_clause ~fresh:false bag 0 (fun _ -> true)
Terms.Demodulation (ctx newside) subst id id2 pos dir clause_ctx
with
| None -> assert false
- | Some (bag,(id,_,_,_,_),lit) ->
+ | Some (bag,_,(id,_,_,_,_),lit) ->
(bag,newside,id,lit)
;;
Some ((bag,id2,lit),jump_to_right)
;;
- let rec demodulate bag (id,nlit,plit,vl,proof) table =
+ let rec demodulate_old bag (id,nlit,plit,vl,proof) table =
let rec demod_lit ~jump_to_right bag id lit clause_ctx =
match demodulate_once ~jump_to_right bag id lit vl table clause_ctx with
| None -> bag, id, lit
| Some ((bag, id, lit),jump) ->
demod_lit ~jump_to_right:jump bag id lit clause_ctx
in
- (*let cmp_bag,cmp_cl = match nlit,plit with
+ (*match nlit,plit with
|[],[lit,_] ->
let bag, id, lit = demod_lit ~jump_to_right:false bag id lit (fun l -> nlit, [l,true])
in
in
let cl,_,_ = Terms.get_from_bag id bag in
bag,cl
- |_ -> assert false
- in*)
+ |_ -> assert false*)
let nlit,_,bag,id = if nlit = [] then nlit,[],bag,id
else List.fold_left
(fun (pre,post,bag,id) (lit,sel) ->
with FoUnif.UnificationFailure _ -> false)
| _ -> false
- let build_new_clause bag maxvar filter rule t subst id id2 pos dir =
- let maxvar, _vl, subst = Utils.relocate maxvar (Terms.vars_of_term
- (Subst.apply_subst subst t)) subst in
- match build_clause bag filter rule t subst id id2 pos dir (fun x -> [],[(x,true)]) with
- | Some (bag, c, _) -> Some ((bag, maxvar), c)
- | None -> None
- ;;
- let prof_build_new_clause = HExtlib.profile ~enable "build_new_clause";;
- let build_new_clause bag maxvar filter rule t subst id id2 pos x =
- prof_build_new_clause.HExtlib.profile (build_new_clause bag maxvar filter
- rule t subst id id2 pos) x
- ;;
-
- let fold_build_new_clause bag maxvar id rule filter res =
+ let fold_build_new_clause bag maxvar id rule filter res clause_ctx =
+ debug (lazy (string_of_int (List.length res)));
let (bag, maxvar), res =
HExtlib.filter_map_acc
(fun (bag, maxvar) (t,subst,id2,pos,dir) ->
- build_new_clause bag maxvar filter rule t subst id id2 pos dir)
+ match build_clause ~fresh:true bag maxvar filter
+ rule t subst id id2 pos dir clause_ctx with
+ | None -> None
+ | Some (bag,maxvar,res,_) -> Some ((bag,maxvar),res))
(bag, maxvar) res
in
bag, maxvar, res
let is_subsumed ~unify bag maxvar (id, nlit, plit, vl, _) table =
match nlit,plit with
+ | [Terms.Equation (l,r,ty,_) ,_],[]
| [],[Terms.Equation (l,r,ty,_) ,_]->
(match rewrite_eq ~unify l r ty vl table with
| None -> None
| Some (id2, dir, subst) ->
let id_t = Terms.Node [ Terms.Leaf B.eqP; ty; r; r ] in
- build_new_clause bag maxvar (fun _ -> true)
- Terms.Superposition id_t subst id id2 [2] dir)
+ build_clause ~fresh:true bag maxvar (fun _ -> true)
+ Terms.Superposition id_t subst id id2 [2] dir (fun l -> [],[l,true]))
| _ -> None (* TODO : implement subsumption for clauses *)
;;
let prof_is_subsumed = HExtlib.profile ~enable "is_subsumed";;
let rec deep_eq ~unify l r ty pos contextl contextr table acc =
match acc with
| None -> None
- | Some(bag,maxvar,(id,nlit,plit,vl,p),subst) ->
+ | Some(bag,maxvar,(id,nlit,plit,vl,p as cl),subst) ->
let l = Subst.apply_subst subst l in
let r = Subst.apply_subst subst r in
try
let subst1 = Unif.unification (* vl *) [] l r in
let lit =
match nlit,plit with
- | [],[Terms.Equation (l,r,ty,o),_] ->
+ | [Terms.Equation (l,r,ty,o),_],[] ->
Terms.Equation (FoSubst.apply_subst subst1 l,
FoSubst.apply_subst subst1 r, ty, o)
- | _ -> assert false
+ | _ -> debug (lazy (Pp.pp_clause cl));assert false
in
- Some(bag,maxvar,(id,[],[lit,true],vl,p),Subst.concat subst1 subst)
+ Some(bag,maxvar,(id,[lit,true],[],vl,p),Subst.concat subst1 subst)
with FoUnif.UnificationFailure _ ->
match rewrite_eq ~unify l r ty vl table with
| Some (id2, dir, subst1) ->
(Terms.Node[Terms.Leaf B.eqP;ty;contextl r;contextr r])
in
(match
- build_new_clause bag maxvar (fun _ -> true)
+ build_clause ~fresh:true bag maxvar (fun _ -> true)
Terms.Superposition id_t
- subst1 id id2 (pos@[2]) dir
+ subst1 id id2 (pos@[2]) dir (fun l -> [l,true],[])
with
- | Some ((bag, maxvar), c) ->
+ | Some (bag, maxvar, c, _) ->
Some(bag,maxvar,c,newsubst)
| None -> assert false)
| None ->
if no_demod then bag, clause else demodulate bag clause table
in
if List.exists (Clauses.are_alpha_eq_cl clause) g_actives then None else
- (debug (lazy (Pp.pp_clause clause));
if (is_goal_trivial clause)
then raise (Success (bag, maxvar, clause))
else
| None -> Some (bag,clause)
| Some (bag,maxvar,cl,subst) ->
prerr_endline "Goal subsumed";
- raise (Success (bag,maxvar,cl)))
+ raise (Success (bag,maxvar,cl))
(*
else match is_subsumed ~unify:true bag maxvar clause table with
| None -> Some (bag, clause)
(* =================== inference ===================== *)
(* this is OK for both the sup_left and sup_right inference steps *)
- let superposition table varlist subterm pos context =
+ let superposition table varlist is_pos subterm pos context =
let cands = IDX.DT.retrieve_unifiables table subterm in
HExtlib.filter_map
- (fun (dir, _, _, (id,nlit,plit,vl,_ (*as uc*))) ->
+ (fun (dir, is_cand_pos, _, (id,nlit,plit,vl,_ (*as uc*))) ->
match nlit,plit with
| [],[Terms.Equation (l,r,_,o),_] ->
(let side, newside = if dir=Terms.Left2Right then l,r else r,l in
+ debug (lazy (Pp.pp_foterm subterm));
+ debug (lazy (Pp.pp_foterm side));
try
let subst =
Unif.unification (* (varlist@vl)*) [] subterm side
if o <> Terms.Lt && o <> Terms.Eq then
Some (context newside, subst, id, pos, dir)
else
- ((*prerr_endline ("Filtering: " ^
- Pp.pp_foterm side ^ " =(< || =)" ^
- Pp.pp_foterm newside);*)None)
+ (debug (lazy "Filtering out..."); None)
else
Some (context newside, subst, id, pos, dir)
with FoUnif.UnificationFailure _ -> None)
;;
(* Superposes selected equation with equalities in table *)
- let superposition_with_table bag maxvar (id,nlit,plit,vl,_) table =
- match nlit,plit with
- | [],[Terms.Equation (l,r,ty,Terms.Lt),_] ->
+ let superposition_with_table bag maxvar id vl lit is_pos clause_ctx table =
+ match lit with
+ | Terms.Equation (l,r,ty,Terms.Lt) ->
fold_build_new_clause bag maxvar id Terms.Superposition
(fun _ -> true)
(all_positions [3]
(fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; l; x ])
- r (superposition table vl))
- | [],[Terms.Equation (l,r,ty,Terms.Invertible),_]
- | [],[Terms.Equation (l,r,ty,Terms.Gt),_] ->
+ r (superposition table vl is_pos)) clause_ctx
+ | Terms.Equation (l,r,ty,Terms.Invertible)
+ | Terms.Equation (l,r,ty,Terms.Gt) ->
fold_build_new_clause bag maxvar id Terms.Superposition
(fun _ -> true)
(all_positions [2]
(fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; x; r ])
- l (superposition table vl))
- | [],[Terms.Equation (l,r,ty,Terms.Incomparable),_] ->
+ l (superposition table vl is_pos)) clause_ctx
+ | Terms.Equation (l,r,ty,Terms.Incomparable) ->
let filtering avoid subst = (* Riazanov: p.33 condition (iv) *)
let l = Subst.apply_subst subst l in
let r = Subst.apply_subst subst r in
(filtering Terms.Gt)
(all_positions [3]
(fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; l; x ])
- r (superposition table vl))
+ r (superposition table vl is_pos)) clause_ctx
in
let bag, maxvar, l_terms =
fold_build_new_clause bag maxvar id Terms.Superposition
(filtering Terms.Lt)
(all_positions [2]
(fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; x; r ])
- l (superposition table vl))
+ l (superposition table vl is_pos)) clause_ctx
in
bag, maxvar, r_terms @ l_terms
| _ -> assert false
;;
+ let superpose_literal id vl table is_pos (bag,maxvar,pre,post,acc) (lit,sel) =
+ let clause_ctx =
+ if is_pos then fun l -> [],pre@[l,true]@post
+ else fun l -> pre@[l,true]@post,[]
+ in
+ let bag, maxvar, newc =
+ superposition_with_table bag maxvar id vl lit is_pos clause_ctx table
+ in
+ if post = [] then bag,maxvar,pre@[lit,sel],[],newc@acc
+ else bag,maxvar,pre@[lit,sel],List.tl post,newc@acc
+ ;;
+
+
(* the current equation is normal w.r.t. demodulation with atable
* (and is not the identity) *)
let infer_right bag maxvar current (alist,atable) =
(* We superpose active clauses with current *)
let bag, maxvar, new_clauses =
List.fold_left
- (fun (bag, maxvar, acc) active ->
- let bag, maxvar, newc =
- superposition_with_table bag maxvar active ctable
+ (fun (bag, maxvar, acc) (id,nlit,plit,vl,_) ->
+ let bag, maxvar, _, _, acc =
+ if nlit = [] then bag,maxvar,[],[],acc
+ else List.fold_left
+ (superpose_literal id vl ctable false) (bag,maxvar,[],List.tl nlit,acc) nlit
in
- bag, maxvar, newc @ acc)
+ let bag, maxvar, _, _, acc =
+ if plit = [] then bag,maxvar,[],[],acc
+ else List.fold_left
+ (superpose_literal id vl ctable true) (bag,maxvar,[],List.tl plit,acc) plit
+ in
+ bag, maxvar, acc)
(bag, maxvar, []) alist
in
debug (lazy "First superpositions");
let fresh_current, maxvar = Clauses.fresh_clause maxvar current in
(* We need to put fresh_current into the bag so that all *
* variables clauses refer to are known. *)
- let bag, fresh_current = Terms.add_to_bag fresh_current bag in
+ let bag, (id,nlit,plit,vl,_) = Terms.add_to_bag fresh_current bag in
(* We superpose current with active clauses *)
- let bag, maxvar, additional_new_clauses =
- superposition_with_table bag maxvar fresh_current atable
+ let bag, maxvar, _, _, additional_new_clauses =
+ if nlit = [] then bag,maxvar,[],[],[]
+ else List.fold_left
+ (superpose_literal id vl atable false) (bag,maxvar,[],List.tl nlit,[]) nlit
in
+ let bag, maxvar, _, _, additional_new_clauses =
+ if plit = [] then bag,maxvar,[],[],[]
+ else List.fold_left
+ (superpose_literal id vl atable true) (bag,maxvar,[],List.tl plit,additional_new_clauses) plit
+ in
debug (lazy "Another superposition");
- let new_clauses = new_clauses @ additional_new_clauses in
+ let new_clauses = new_clauses@additional_new_clauses in
debug (lazy (Printf.sprintf "Demodulating %d clauses"
(List.length new_clauses)));
let bag, new_clauses =
(* We superpose the goal with active clauses *)
if (match goal with (_,_,_,[],_) -> true | _ -> false) then bag, maxvar, []
else
- let bag, maxvar, new_goals =
- superposition_with_table bag maxvar goal atable
+ let (id,nlit,vl) =
+ match goal with
+ | (id,nlit,[],vl,_) -> id,nlit,vl
+ | _ -> assert false
+ in
+ let bag, maxvar, _, _, new_goals =
+ List.fold_left (superpose_literal id vl atable false)
+ (bag,maxvar,[],List.tl nlit,[]) nlit
in
- debug (lazy "Superposed goal with active clauses");
+ debug (lazy (string_of_int (List.length new_goals) ^ " new goals"));
(* We simplify the new goals with active clauses *)
let bag, new_goals =
List.fold_left
projects / helm.git / blobdiff